Amid ongoing violence and the threat of famine, South Sudan is marking four years of independence from Sudan.

South Sudan became the world's newest nation in 2011 following a vote to secede from northern neighbor Sudan.

But the young country fell into war after just 18 months as a result of a political dispute between President Salva Kiir and his former deputy Riek Machar.

The prominent South Sudanese activist Edmund Yakani said that there is "nothing that we can celebrate" about the independence anniversary.

Aimee Ansari of CARE International said that as South Sudan's conflict continues, "the malnutrition numbers that we're seeing now make me profoundly concerned that too many children in this country won't reach their fifth birthday."